Field of Disclosure
The embodiments described herein relate generally to the internal inspection of railway track components using x-ray and neutron imaging techniques. More particularly, the embodiments described herein relate to backscatter and transmission radiography techniques for internal inspection of railway track components.
Related Art
Currently, flaws in rails and other railway track components are detected through direct contact non-destructive methods, such as ultrasound, or through destructive methods. The negative consequences of the latter are obvious whereas the former may leave flaws undetected in the rail, or identify “false positives” when in fact no defect exists. One known way to detect these flaws is with a handheld ultrasound system.
Currently, some flaws may be detected using destructive methods. One such flaw is an under shell fracture in a rail that may not be detectable with known non-destructive method. Such a defect is important to find so as to prevent catastrophic rail failure leading to derailment of rail bound vehicles. Additional flaws may include Rail Base Corrosion (RBC). Although RBC can be found on any track, it is most prevalent in tunnels and/or where the track is electrified. This is due to the combination of the standing water and electricity flowing through the rail acting to rust and erode the rail-base at an increased rate.
Approximately 15.3% of all derailments between 2001 and 2010 were caused by broken rails or welds. The second most common cause of derailments accounted for only 7.3%, leaving the detection of rail flaws as the most significant factor for the reduction of train derailments. Known inspection methods may leave flaws undetected, leaving significant room for improvement.